/* base */*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:#233742;background:#f5f8fa;font:16px/1.85 -apple-system,BlinkMacSystemFont,"Segoe UI","Microsoft YaHei",sans-serif}a{color:inherit;text-underline-offset:5px}a:hover{color:#19727c}a:focus-visible,summary:focus-visible{outline:3px solid #d58738;outline-offset:4px}p{margin:0 0 18px}h1,h2,h3{margin:0 0 20px;line-height:1.38}h1{font-size:clamp(34px,4vw,54px);letter-spacing:-.035em}h2{font-size:28px;letter-spacing:-.02em}h3{font-size:21px}img{max-width:100%;display:block}figure{margin:0}.jump{position:absolute;left:-9999px}.jump:focus{left:10px;top:8px;z-index:10;background:#fff;padding:10px}/* layout */.book-header,main,.book-footer{max-width:1160px;margin:auto;padding-left:35px;padding-right:35px}.book-header{min-height:94px;display:flex;align-items:center;justify-content:space-between;gap:24px}.book-header nav{display:flex;gap:27px;font-size:14px}.book-header nav a{text-decoration:none}.wordmark{display:flex;gap:12px;align-items:baseline;font-size:24px;font-weight:780;text-decoration:none}.wordmark span{font-size:15px;font-weight:500}.book-opening{background:#dbeaf0}.opening-copy{padding:45px 45px 35px;max-width:850px}.opening-copy>p:not(.eyebrow){max-width:650px;color:#4d646f;font-size:18px}.opening-image{height:330px;overflow:hidden}.opening-image img{height:100%;width:100%;object-fit:cover;object-position:50% 50%}.eyebrow,.topic{font-size:12px;letter-spacing:.07em;color:#407a85;font-weight:650}.primary{display:inline-flex;align-items:center;padding:13px 23px;min-height:48px;text-decoration:none;background:#163f52;color:#fff;font-weight:650}.primary:hover{background:#275e69;color:white}.handbook-layout{display:grid;grid-template-columns:220px 1fr;gap:58px;padding:55px 0}.chapter-nav{align-self:start;position:sticky;top:25px;border-left:3px solid #669aa6;padding-left:20px;font-size:14px}.chapter-nav p{font-size:12px;font-weight:700;color:#597481}.chapter-nav nav{display:flex;flex-direction:column;gap:14px}.chapter-nav a{text-decoration:none}.chapter{padding:0 0 38px;margin:0 0 38px;border-bottom:1px solid #c6d6dd;scroll-margin-top:24px}.chapter:last-child{margin:0;padding-bottom:0;border:0}.lead-answer{font-size:20px;color:#264d60;line-height:1.8}.text-link{font-weight:650;font-size:15px}.address{font-family:ui-monospace,SFMono-Regular,Consolas,monospace;overflow-wrap:anywhere}.checkpoint{margin:28px 0;border-top:1px solid #bfd2dc}.checkpoint>div{display:grid;grid-template-columns:140px 1fr;gap:20px;padding:18px 0;border-bottom:1px solid #bfd2dc}.checkpoint dt{font-weight:650}.checkpoint dd{margin:0;font-size:15px}.note{border-left:4px solid #c3864e;background:#eee7dd;padding:20px 24px;margin:26px 0}.note p{font-size:15px;margin:8px 0 0}.result-list{padding-left:22px}.result-list li{margin:14px 0}.guides{padding:32px 0 45px;border-top:3px solid #274b5b}.handbook-links{display:grid;grid-template-columns:1fr 1fr;gap:40px}.handbook-link{padding:20px 0;border-top:1px solid #b9cdd6}.handbook-link h3 a{text-decoration:none}.handbook-link>p:last-child{font-size:14px;color:#617783}.small-answers{padding:15px 0 60px;max-width:800px}.small-answers details{border-bottom:1px solid #bfd2dc;padding:19px 0}.small-answers summary{cursor:pointer;font-weight:600}.small-answers details p{padding-top:16px;color:#4f6874;font-size:15px}.book-footer{border-top:1px solid #c4d4db;padding-top:30px;padding-bottom:35px;display:flex;justify-content:space-between;gap:45px}.book-footer strong{font-size:18px}.book-footer p{font-size:12px;color:#657b86;max-width:620px;margin-top:8px}.book-footer nav{display:flex;gap:24px;white-space:nowrap;align-self:start;font-size:12px}.plain-page{max-width:920px;padding-top:45px;padding-bottom:65px;min-height:65vh}.plain-page h1{font-size:40px}.plain-page h2{font-size:25px;margin-top:36px}.plain-page .handbook-links{display:block;margin-top:40px}.plain-page .handbook-link{padding:25px 0}.breadcrumbs{display:flex;flex-wrap:wrap;gap:12px;font-size:12px;padding:20px 0;color:#647d89}.paper-heading{background:#e3eef3;padding:34px 40px 30px}.paper-heading h1{font-size:40px;max-width:900px}.article-answer{font-size:19px;line-height:1.8;color:#41616f}.paper-heading time{font-size:12px;color:#68818c}.paper-layout{display:grid;grid-template-columns:180px 1fr;gap:48px;padding:40px 0 65px}.article-contents{position:sticky;top:25px;align-self:start;display:flex;flex-direction:column;gap:12px;font-size:13px;padding-top:8px}.article-contents p{margin-bottom:5px;font-weight:700;color:#5e7a87}.article-contents a{text-decoration:none}.manual-body{max-width:760px;font-size:17px}.manual-body section{scroll-margin-top:25px;margin-bottom:42px}.manual-body section:last-child{margin-bottom:0}.manual-body h2{font-size:27px;margin-bottom:21px}.manual-body .note{margin:25px 0}/* responsive */@media(max-width:760px){.book-header,main,.book-footer{padding-left:20px;padding-right:20px}.book-header{display:block;padding-top:18px;padding-bottom:18px;min-height:0}.wordmark{font-size:23px}.wordmark span{font-size:14px}.book-header nav{gap:23px;font-size:12px;margin-top:12px}.opening-copy{padding:26px 24px}.opening-copy h1{font-size:33px}.opening-copy>p:not(.eyebrow){font-size:16px}.primary{font-size:14px;padding:13px 17px}.opening-image{height:235px}.opening-image img{object-position:60% 50%}.handbook-layout{display:block;padding:30px 0}.chapter-nav{position:static;border-left:0;border-bottom:1px solid #c6d6dd;padding:0 0 20px;margin-bottom:30px}.chapter-nav p{margin-bottom:12px}.chapter-nav nav{flex-direction:row;flex-wrap:wrap;gap:8px 20px;font-size:13px}.chapter{margin-bottom:30px;padding-bottom:30px}.chapter h2{font-size:25px}.lead-answer{font-size:18px}.checkpoint>div{display:block;padding:17px 0}.checkpoint dt{margin-bottom:5px}.note{padding:17px 19px}.handbook-links{grid-template-columns:1fr;gap:5px}.guides{padding-top:27px}.guides h2,.small-answers h2{font-size:26px}.small-answers{padding-bottom:40px}.book-footer{display:block}.book-footer nav{margin-top:20px;gap:25px}.plain-page{padding-top:30px}.plain-page h1{font-size:33px}.paper-heading{padding:25px 23px}.paper-heading h1{font-size:29px}.article-answer{font-size:17px}.paper-layout{display:block;padding-top:25px}.article-contents{position:static;flex-direction:row;flex-wrap:wrap;gap:8px 20px;border-bottom:1px solid #bfd2dc;padding-bottom:22px;margin-bottom:28px}.article-contents p{width:100%}.manual-body{font-size:16px}.manual-body h2{font-size:25px}.manual-body section{margin-bottom:35px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}